Nov. 12, 2026
Before a Data Center E House leaves the Pushen factory, we use a documented factory acceptance testing (FAT) process to verify electrical safety, mechanical integrity, environmental protection, control logic, and transport readiness. By following the step-by-step inspection method below, project owners, EPC contractors, and data center operators can reduce commissioning delays, identify defects before delivery, and receive a tested modular power building that is ready for efficient site installation.
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A Data Center E House—also called an electrical house, e-house, modular substation, or prefabricated power building—contains critical systems such as:
These systems must operate as one integrated package. A small wiring error, incorrect relay setting, loose busbar joint, or damaged enclosure can create serious problems during site commissioning.
At Pushen, we treat factory testing as a risk-control process rather than a final visual inspection. The objective is to verify the design, workmanship, interfaces, and operating sequence before the Data Center E House is disconnected, packed, and transported to the project site.
The exact test plan depends on the project specification, voltage level, environmental conditions, and applicable standards. However, a complete factory inspection normally follows the sequence below.
We begin by checking that the manufactured unit matches the approved engineering documents.
The quality team reviews:
The inspectors confirm equipment tags, cable numbers, component ratings, panel locations, door swing directions, maintenance clearances, and access routes.
For international projects, we also verify the required electrical and enclosure standards. Common references include:
This document review prevents a common project problem: a unit that is manufactured correctly but does not match the latest revision of the customer’s design.
Next, Pushen checks the E-House structure, base frame, roof, walls, doors, cable entries, and lifting points.
We verify:
Critical dimensions can be measured to a tolerance of 0.01 mm where the project specification requires precision inspection. Larger structural dimensions are checked against the approved manufacturing tolerance and transport drawings.
This step is particularly important for Prefabricated Electrical Enclosures because the E-House must connect precisely with external cable trenches, transformers, generator systems, cooling equipment, and civil foundations.
We also inspect weld quality, coating condition, fasteners, gaskets, insulation, and corrosion protection. Weld examination may include visual inspection and, when specified, non-destructive testing such as dye penetrant or ultrasonic testing.
After the structure is approved, we inspect the internal electrical installation.
The inspection team checks:
Every accessible termination is checked using a calibrated torque wrench. The actual torque value is compared with the manufacturer’s instruction, and the result is recorded in the FAT documentation.
For a large project, Pushen may perform 100% visual and termination inspection rather than relying only on sampling. This gives the customer a traceable inspection record for every panel, cable, and major connection.
Once the assembly inspection is complete, we conduct electrical tests under controlled factory conditions.
Insulation resistance testing confirms that conductors, busbars, and connected circuits are adequately insulated from each other and from earth.
Typical activities include:
The acceptance criteria depend on voltage class, equipment type, and the applicable IEC or project standard. We do not apply one universal value to every system because sensitive UPS electronics, protection relays, and communication devices may require specific test arrangements.
A reliable grounding system is essential for personnel safety and fault-current clearance.
Pushen verifies:
A low-resistance continuity test is recorded for critical bonding paths. Any painted or coated connection point is checked to ensure that the bonding method provides a dependable electrical path.
The next stage verifies that equipment operates correctly under normal, abnormal, and interlocked conditions.
We test:
Protection relays are tested using secondary injection equipment where required. The test engineer confirms pickup values, trip times, alarm settings, and communication signals against the approved protection study.
For a data center, this test is especially valuable because a defective interlock or incorrect transfer sequence can interrupt redundant power paths during commissioning.
A Data Center E House is not only an electrical enclosure. Its auxiliary systems must maintain safe operating conditions for energized equipment.
Pushen checks:
The HVAC system is tested against the approved heat-load calculation. We verify that the cooling arrangement can support the expected equipment losses under the project’s design conditions.
Where fire protection is installed, the sequence of alarm, shutdown, damper operation, and suppression release interface is tested without unnecessarily discharging the extinguishing agent.
| Test category | Main verification | Typical evidence |
|---|---|---|
| Design review | Approved drawings and revisions | Document review record |
| Structural inspection | Dimensions, welds, doors, roof, lifting points | Dimensional report |
| Enclosure protection | Seals, cable entries, IP design | Inspection checklist |
| Electrical assembly | Components, labels, wiring, torque | Torque and wiring records |
| Insulation test | Phase-to-phase and phase-to-earth insulation | Megger test report |
| Dielectric test | Electrical withstand performance | Hi-pot test record |
| Grounding | Earth continuity and bonding | Grounding report |
| Functional test | Breakers, interlocks, trips, alarms | Functional test sheet |
| Protection test | Relay settings and trip times | Secondary injection report |
| HVAC test | Cooling, heating, ventilation, alarms | HVAC commissioning record |
| Fire and safety test | Detection, emergency stop, lighting | Safety system report |
| Transport readiness | Lifting, packing, supports, protection | Pre-shipment checklist |
After internal testing, Pushen organizes a formal customer or third-party FAT when required by the contract.
The customer’s representatives may review:
A successful FAT should not depend on verbal confirmation. Each test result should be recorded, signed, and linked to the relevant equipment tag or drawing reference.
For complex Prefabricated Electrical Enclosures, the FAT may include a live control demonstration. This allows the customer to observe the complete sequence from incoming power detection to breaker operation, alarm generation, remote monitoring, and emergency shutdown.
Pushen can also provide a FAT agenda in advance so that project stakeholders know:
A frequent issue is that the factory receives a drawing revision different from the customer’s latest approved version.
Solution: We establish a document register, revision-control process, and hold point before production. No critical test should begin until the relevant drawings are confirmed.
UPS modules, relays, controllers, and communication devices may be affected by incorrect insulation or dielectric testing.
Solution: We follow the equipment manufacturer’s isolation requirements and use a controlled test procedure. Sensitive components are disconnected or protected before applying test voltage.
Modbus, Ethernet, hardwired I/O, and building management system interfaces can fail because of incorrect addressing, polarity, mapping, or protocol configuration.
Solution: We perform point-to-point checks, verify I/O lists, confirm communication addresses, and simulate alarm and status signals before shipment.
Even a fully tested E-House can be damaged if doors, filters, instruments, or internal equipment are not protected during transport.
Solution: We install transport braces, lock moving components, protect cable glands and ventilation openings, secure loose parts, and complete a final photographic inspection.
Minor defects can become major site delays if they are not assigned and closed properly.
Solution: Each finding receives a responsible person, target date, corrective action, and closure evidence. Pushen typically provides a documented response within 24 hours for urgent FAT findings, subject to project communication arrangements.
A structured testing program becomes more reliable when supported by the correct tools and records.
Useful resources include:
All measuring equipment should have a valid calibration certificate traceable to a recognized laboratory. Test results should include the instrument ID, calibration expiry date, test conditions, operator, and acceptance criteria.
Thermal imaging is also useful after energization or simulated loading. It can identify abnormal heating at cable lugs, busbar joints, breakers, and connection points before the unit is packed.
Before loading the Data Center E House, Pushen completes a final release inspection.
We confirm that:
The E-House is then inspected for cleanliness, water ingress, loose components, missing hardware, and cosmetic damage. Photographs provide additional evidence of the condition at the time of release.
To make the project handover more efficient, customers should request the following documents before shipment:
These documents help the site team compare the delivered equipment with the factory-approved condition. They also reduce repeated testing and accelerate energization.
The most effective pre-shipment strategy is simple: control the documents, inspect the structure, test every critical electrical function, verify auxiliary systems, close punch-list items, and protect the unit for transport.
When Pushen applies this process to Data Center E Houses and Prefabricated Electrical Enclosures, project teams gain a clear record of what was tested, how it was tested, and whether the results met the approved criteria. The result is fewer installation surprises, faster site commissioning, improved personnel safety, and greater confidence in the complete modular power system.
For your next project, request the Pushen FAT plan early, confirm the applicable IEC, ASTM, or DIN requirements, nominate customer witness points, and review the complete test dossier before shipment. This practical preparation is how a tested factory assembly becomes a reliable operating asset at the project site.
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